Ladder



' M y 0, 1944! I H. w. RICHARDS 2,350,129

LADDER Filed July 20, 1945 2 Sheets-Sheet 1 y 1944- H. w. RICHARDS 12,350,129

' LADDER Filed July. 20, 1943 2 Sheets-Sheet 2 Patented May 30, 1944UNITED STATES i TENT OFFICE LADDER Hugh W. Richards, Carrollton, Ga;Application July 20, 1943, Serial No, 195,484

5 Claims.

The present invention relates to an improved ladder and moreparticularly to a combined extension and step-ladder formed of separatesections provided with means whereby the sections may be placedend-to-end to increase the length of the ladder or may be removed fromone another and used as individual ladders or converted into either apair of short step-ladders or a long stepladder.

An important feature of the invention consists in providin simple,eflicient, and economical means for securing and removably interlockingadjacent sections of the ladder together to form a safe, strong, anddurable extension ladder. lAdditionally, means are provided so that thesections may be selectively connected to form a pair of shortstep-ladders or a long step-ladder,

Other objects and advantages of the invention will become apparent fromthe following description when taken in conjunction with theaccompanying claims and drawings.

Referring to the drawings, in which is disclosed a preferred embodimentof the invention Figure 1 is a perspective view showing the sections ofthe ladder prior to being assembled;

Figure 2 is a perspective view showing the sections combined to form twoshort step-ladders;

Figure 3 is a perspective view showing the sections arranged to form alarge step-ladder;

Figure 4 is a perspective view of the sections connected together toform an extension ladder; I

Figure 5 is an enlarged detail sectional view taken along the line 55 ofFigure 4;

Figure 6 is a detail sectional View taken substantially along the line6-6 of Figure 5, and

Figure 7 is a sectional View taken substantially along the line 1-1 ofFigure 5.

The combined extension and step-ladder may be composed of two or moresections and preferably comprises four separate sections A, B, C, and D,respectively (Figure 1), each of which has spaced side bars l and IIconnected by transverse rungs !3. The sections A and C are of the samewidth and are wider than the sections B and D, and preferably all thesections are of the same length. The section A constitutes the base ofthe extension ladder, and the side bars B and II thereof adjacent theupper end ar provided with transversely aligned bayonet slots M in thesides thereof, each of these slots having a transverse opening Li thatcommunicates with a vertical elongated slot l6 that extends downwardlybelow the adjacent wall of the slot l5 so as to form a retaining notchor shoulder H. The section A carries a spacing or locking member I8which is pivotally connected at one end as at l9 to one of the rungs l3and has its opposite or free end formed with a notch 20, the purpose ofwhich will subsequently be described. The upper ends of the side bars l0and II of each of sections B and C are providedwith bayonet slots l-4similar in construction to the slots in section A and also have theirlower ends provided with bayonet slots 2| provided with curved shouldersor'retaining.

portions 22 that extend upwardly as contrasted to the downwardlyextending shoulder portions H in the upper ends of these sections. Thetop rung 23'and the lower rung 23' of section B have their endsextending outwardly from the side bars l9 and II, to form the trunnions24. The lower rung l3 of the section C has pivotally connected theretoas at 25, a locking bar or me'mber 26, and the opposite end of thismember is formed with a slot,2l. The section D which constitutes the topportion of the extension ladder has the lower ends'of its side bars l0and H provided with bayonet slots 28 similar in shape to the slots 21and also has its upper rung 29 and its lower rung 3|] formed withoutwardly protruding extensions or trunnions 3| A bar or member 32 ispivoted adjacent one end as at 33'to one of the rungs I3, and at itsopposite end is formed with a slot 34. The sections A and C are of thesame width and constitute a pair ofwide sections and the sections B andD are of the samewidth to form a pair of narrow 'sections capable ofbeing selectively interconnected to form ladders of different Assumingit is desired to form an extension ladder, the section A which is Widerthan the section B is positioned to constitute the base of the ladder,and the lower portion of the section B is positioned between the sidebars I0 and H of section A, so that the bayonet slots 2| therein willregister with the adjacent upper rung N of section A, and the lowertrunnions 24 will fit with in the adjacent slots l4. Upon moving thesection B downwardly relative to the section A, the end rungs slide intolocking engagement withthe shoulder portions ll and 22 in the slots l4and 2|, respectively, thus insuring the sections being securely andfirmly maintained in locking en gagement until released by the rungsbeing moved into alignment with the transverse openings 15 of the lots.The lower portion of the section C is moved. into overlapping positionrelative to the upper portion of the section B so that the bayonet slots2! in the section 0 engage the upper trunnions in the section B and thelower .-rung in section C fits within theadjacent upper slots M of thesection B, and upon movement of the section C downwardly relative to thesection B, the bayonet slots are caused to be maintained in lockingengagement with the adjacent rungs to interlock the sections together.The member 26 may then be swung about its pivot so that the notch 21 inthe free end thereof is moved into engagement with the adjacent rung ofthe section B in order to further insure these sections being positivelylocked. The lower portion of the upper section D is now moved to fitbetween the side bars I and I I of the section C so that the bayonetslots 28 thereof engage the adjacent upper rung l3 of the section C, andthe lower trunnions 3| fit within the bayonet slots M of section C, andupon the section D being moved downwardly relative to the section C, thebayonet slots cause the adjacent rungs to be interlocked therewith torigidly secure the sections in position. The pivotal bar or member 26thus provides an auxiliary locking means which coacts with the bayonetslots to insure the adjacent sections being firmly maintained inposition.

The length of the extension ladder may be adjusted to lengthen orshorten the same by adding one or more sections to the base section orit may be shortened by removing one or more of the upper sections. Theassembled sections now assume the position shown in Figure 4, and may beplaced against a wall or the like E to provide an extension ladder ofany desired length.

Thusit will be seen that the separate sections are constructed andarranged so that they may be conveniently set up end-to-end to form arigid and durable extension ladder at a minimum expenditure of time andeffort and in which the bayonet slots coact with adjacent rungs tosecurely and removably interlock'the adjacent sections together. Thebayonet slot joints are positioned on the overlapping portions of thesections and are detachably connected to the adjacent rungs on eitherthe outside or inside of the side bars in such a manner that the weightor pressure applied to the'front or outside of the extension laddercauses thisweight to be transferred and carried directly by the rungswithout danger of a breaking action or the sagging of the ladder. M Thisnovel and positive interlocking connection is'clearlyshown in Figure inwhich it will be observed that the pressure or weight applied tothefront of the ladder is transferred by the notched portions or shouldersof the bayonet slots directly to the spaced rungs I3 and 23', thusinsuring the overlapped portions being firmly locked together andretained in this locked position until the rungs are moved out ofcontact with the shoulders. Further, the co-action of the bayonet slotswith the rung provides a simple and highly efiicient ladder structurewhich is composed of a minimum number, of parts and may be inexpensivelymade without sacrificing strength and rigidity. The ladder is preferablymade of wood and dispenses with the use of removable rungs which notinfrequently are difficult to manipulate, and eliminates expensive andheavy metallic parts such as independently movable locking elements. Thebayonet slots in the end portions of the overlapped sections providespaced means which are locked in engagement with the rungs on adjacentsections both inside and outside of the side bars in and II and operateso that the greater the pressure applied to the overlapped portions, thestronger and more rigid will the locking means act to secure thesections together.

This is a very desirable and essential 7 feature since once theextension ladder has been properly assembled it may be safely usedwithout danger of the sections accidentally being disconnected. In fact,the strongest parts of the ladder are now at the overlapped portionswhich are rigidly and firmly connected by the spaced interlockingengagement of the slots with their adjacent rungs, and this connectioncannot be released until the rungs are removed from the slots.

When it is desired to dismantle the extension ladder, this may be easilydone by sliding the rungs of each section out of engagement with theshoulder portions of the bayonet slots so that the sections may beremoved and arranged in a compact pile for further use or fortransportation purposes.

If it is desired to form one or two small stepladders, then the sectionA is combined with the section B so that the lower rung 35 nowconstitutes the upper rung (Figure 2) and may receive either the bayonetslots M or the slots 2| in the section B so as to be pivotally connectedthereto. The bar I8 is then swung about its pivot, so that its slot 20will engage the adjacent rung in section B to maintain the sections orlegs A and B in proper spaced position. The rung 29of the section D maylikewise be moved into pivotal engagement with the bayonet slots I4 inthe section C and the bar 32 swung about its pivot so that the notch 34thereof engages the adjacent rung on the section C to maintain thesections C and D properly spaced from each other.

The separate sections may further be converted to a large step-ladder byconnecting the sections A and D together and the sections B and C toform the legs of the ladder, and then connecting the bayonet slots M inthe upper end of the section C to the projecting trunnions 3| on the toprung of the section D. The legs of the ladder are maintained in properspaced position by the slot 34 in the pivotal member 32, being movedinto engagement with the adjacent rung l3 on the section C. The rungsmay be secured to the side bars by any suitable means such as the nails36 (Figure 1) and reinforcing nails 31 may be provided to strengthen theend portions of the side bars.

It will be understood that the forms of the invention shown anddescribed are merely illustrative of preferred embodiments and that suchchanges may be made as fall within the purview of one skilled in the artand the scope of the claims.

I claim:

1. A ladder comprising separate sections having side bars and connectingrungs, said sections arranged to be connected end-tO-end to form anextension ladder, the adjacent sections of the ladder being of differentwidths so that the end portions of the wide section overlap the endportions of the narrow section when the extension ladder is assembled,and the overlapped portions of the side bars of each section havingbayonet slots adapted to receive and be moved into locking engagementwith a rung of the adjacent section to rigidly and securely connect theend portions of the wide section overlap the end portions of the narrowsection when the extension ladder is assembled, the overlapped portionsof the side bars of each section having bayonet slots adapted to receiveand be moved into locking engagement with a rung of the adjacent sectionto rigidly and securely connect the sections of the ladder together, andthe end rung of the overlapped narrow section extending beyond the sidebars to provide trunnions for receiving the bayonet slots in theadjacent wide section so that the adjacent sections are rigidlyconnected by spaced means disposed on the inside and outside of the side'bars.

3. A ladder comprising separate sections having side bars and connectingrungs, said sections arranged to be connected end-to-end to provide anextension ladder, alternate sections of the ladder being substantially0f the same width and wider than the remaining sections to provide Wideand narrow sections having overlapped end portions when the extensionladder is assembled, the end rungs of the narrow sections extendingoutwardly from the side bars, the side bars of each section adjacenteach end thereof having bayonet slots adapted to receive and be movedinto locking engagement with rungs on the adjacent sections to securethe sections of the ladder together, and auxiliary locking meanspivotally connected to a rung of one section and arranged to engage therung of an adjacent section.

4. A ladder comprising separate sections having side bars and connectingrungs, said sections arranged to be connected end-to-end to provide anextension ladder, alternate sections of the ladder being substantiallyof the same width and wider than the remaining sections to provide wideand narrow sections having overlapped end portions when the extensionladder is assembled, the end rungs of the narrower sections extendingoutwardly from the side bars, the side bars adjacent the ends thereofhaving bayonet slots adapted to receive and be moved into lockingengagement with adjacent rungs to secure the sections of the laddertogether, the upper end rung of one of the wide sections arranged toreceive the bayonet slots in one end of one of the narrow sections toprovide a pair of pivotally connected sections having legs divergingfrom the point of connection, and means connected to one of the legs andarranged to engage the other leg for maintaining the legs in spacedposition.

5. A ladder comprising four separate sections formed of side bars andconnecting rungs, said sections arranged to be connected end-to-end toprovide an extension ladder, alternate sections of the ladder beingsubstantially the same Width and wider than the remaining sections toprovide a pair of wide sections and a pair of narrow sections, eachsection having their end portions overlapping the adjacent end portionsof the contiguous sections when the extension ladder is assembled, theoverlapped portions of the side bars adjacent the ends thereof havingbayonet slots adapted to receive and be moved into locking engagementwith adjacent rungs to secure the sections of the extension laddertogether, one of the Wide sections constituting the base section of theladder and one of the narrow sections the top section, the two narrowsections each having its end rungs extending outwardly from the sidebars to receive the bayonet slots in the adjacent sections, the upperend portion of the base section arranged to overlap the lower endportion of the top section and be connected thereto by the bayonet slotsengaging the rungs in the adjacent sections, the upper end portion ofthe other narrow section adapted to be overlapped by the lower endportion of the other Wide section and connected thereto by the bayonetslots engaging the adjacent rungs, the bayonet slots in the upper end ofthe side bars of the last-mentioned section arranged to receive thetrunnions on the upper rung of said top section to provide a pivotalconnection therewith, and a member pivoted to the rung of said topsection and arranged to engage a rung of the adjacent section tomaintain the pivoted connected sections in spaced position.

HUGH W. RICHARDS,

